For example, a conventional fluid device unit in the form of a mass flow controller has, as shown in Patent Document 1, a flow rate sensor or a flow rate control valve, and controls a flow rate of a fluid at a set value by an information processing circuit that is separately or integrally provided.
In addition, recently fluid mechanism including mass flow controllers are required to be slim in order to reduce their footprint.
In order to meet this requirement, the present claimed inventor has been developing a mass flow controller whose length in a width direction, i.e., a direction orthogonal to a longitudinal direction viewed from a plan direction, is very short. This mass flow controller comprises one or a plurality of fluid devices between an input port into which a fluid is introduced and an output port from which the fluid discharges, and a direction connecting the input port and the output port viewed from a plan direction is set in the longitudinal direction.
In accordance with this arrangement, even in case of arranging a plurality of fluid paths in parallel, it is possible to configure an extremely compact flow rate control mechanism by arranging a plurality of mass flow controllers in a state of being adjacent each side surface with the longitudinal direction of the fluid device unit substantially parallel each other.
For this kind of the flow rate control mechanism, in addition to the mass flow controllers, auxiliary external fluid devices, such as open/close valves used at a time when the flow rate is to be completely closed or used to halt the mechanism at an abnormal time, are arranged corresponding to each mass flow controllers. Ordinarily these kinds of external fluid devices are arranged in the front and in the rear of the mass flow controller in the longitudinal direction.
In addition, conventionally, in the semiconductor manufacturing process, various component gases are mixed at a predetermined ratio so as to produce a material gas, and the material gas is supplied to inside of a chamber. In order to provide the material gas to the chamber, for example, a gas supply device as shown in Patent Document 2 and Patent Document 3 is used.
Furthermore, since recently a bore of a wafer is enlarged, there is also a case that the material gas is supplied from gas introducing ports arranged at multiple positions in the same chamber. Then a gas supply device further comprising a distributor to divide the mixed material gas into multiple at an arbitrary flow ratio has been developing.